Investigations to Identify SFRA Measurement Sensitivity for Detecting Faults in Transformers

A common failure mode for power transformers is consequent to mechanical deformation of the core or windings. Core damage is more likely as a result of transportation, while winding damage is more likely to be caused by short circuit type forces. Sweep Frequency Response Analysis (SFRA) is an effective low-voltage, off-line diagnostic tool used for fi nding out any possible winding displacement or mechanical deterioration inside the Transformer, due to large electromechanical forces occurring from the fault currents or due to Transformer transportation and relocation. This paper describe through case studies that SFRA test is more sensitive to detect faults compare to conventional testing method.